Isotopic Tracing of Sources and Cycling of Hazardous Metal Mixtures

危险金属混合物的同位素追踪和循环

• 批准号: 10707895
• 负责人: Alex Halliday
• 金额: $ 18.89万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-21 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10707895
• 关键词: Adsorption; Affect; Area; Arsenic; Biological Markers; Cardiometabolic Disease; Characteristics; Chemicals; Chemistry; Cheyenne; Communities; Community Surveys; Data; Deposition; Development; Distal; Elements; Environment; Environmental Exposure; Environmental Impact; Environmental Pollution; Epidemic; Evolution; Excision; Exposure to; Fractionation; Geographic Distribution; Heart; Human; Human body; Immobilization; Intervention; Ions; Isotopes; Light; Link; Maps; Measurement; Measures; Metal exposure; Metals; Methods; Minerals; Mining; Modeling; Monitor; Mus; Native Americans; North Dakota; Organ; Oxidation-Reduction; Pattern; Play; Population; Precipitation; Privatization; Process; Reaction; Research; Reservations; Resolution; Risk; Risk Reduction; Role; Rural Community; Safety; Sampling; Selenium; Sioux Indians; Site; Solid; Source; South Dakota; Spatial Distribution; Superfund; Testing; Time trend; Tissue Sample; Tissues; Trace Elements; Tracer; Tribes; Universities; Uranium; Urine; Water; aqueous; diagnostic tool; drinking; drinking water; exposed human population; geochemistry; ground water; human data; mineralization; noninvasive diagnosis; novel; novel marker; oxidation; programs; remediation; tool; tribal community; tribal lands; uptake; urinary

Project 2 Summary Native American communities surveyed in the Strong Heart Study (SHS) show markedly higher arsenic (As), uranium (U) and selenium (Se) concentrations in urine relative to the average US population. Much of the exposure to hazardous metal mixtures comes from drinking groundwater contaminated with metals often above safety standards. Tribal lands in the US often coincide with mineral deposits, U mining, and metal(loid) contamination in aquifers. In the Northern Plains, elevated concentrations of U and As in drinking water reflect naturally occurring enrichment in aquifers, as well as the legacy of mining near tribal communities. Project 2 of the Columbia University Northern Plains Superfund Research Program (CUNP-SRP) will use isotopic compositions of U and Se, as these elements are sensitive to redox changes in the aquifer, to infer sources and processes controlling contaminant exposures. Redox chemistry of U and Se controls their aqueous concentrations in groundwater; the oxidized species are mobile and toxic whereas the reduced species are insoluble. Concentrations of dissolved U and Se are affected by multiple processes (e.g., dilution, adsorption, dispersion) and are poor indicators of redox-induced fate and cycling in groundwater. Thus, isotope ratios of dissolved U and Se in groundwater, in tandem with concentrations, are invaluable for studying redox-induced (im)mobilization, and tracing uptake and human exposure. We will use U and Se isotope ratios to characterize redox reactions in groundwater, acquiring unique mechanistic information about the reaction progress. These data will help us define local and more distal sources, and the transport and cycling processes of metals in groundwater within the SHS communities in North/South Dakota. Furthermore, we will develop isotopic tracers of U and Se cycling in humans impacted by environmental exposures. The specific aims are to: (1) Determine spatial distribution pattern of isotope ratios or “isoscapes” of U and Se in groundwater samples. This will use high-resolution data and models from Project 1 to target wells within and around U, As and Se hotspots for isotopic characterization. We will also identify local versus distal sources of contamination around these hotspots. (2) Determine the levels of naturally occurring reductive U and Se removal from groundwater and identify conditions for potential As release based on the temporal evolution of U and Se isotope ratios. We will characterize the redox transformation of U and Se and potential mixing of multiple groundwater sources (if any). (3) Determine human exposure from the environmental contamination using isotopic tracers. We will develop a novel non-invasive method to track metal exposure from U and Se in drinking water. For this, we will measure U and Se isotope ratios in urine to constrain primary exposure sources and affected populations by linking those to water isoscapes and the observational data from Project 3. Our results will help evaluate risk of exposure to hazardous metal mixtures, monitoring and management of contaminated aquifers, and linking exposures to environmental sources using a non-invasive diagnostic tool.

项目2摘要 在强心研究(SHS)中接受调查的美国原住民社区显示，砷(As)含量明显较高， 尿铀(U)和硒(Se)浓度相对于美国平均人口。世界上大部分的 接触有害金属混合物来自饮用被金属污染的地下水，通常是在 安全标准。美国的部落土地通常与矿藏、铀矿开采和金属(矿化)重合。 含水层中的污染。在北部平原，饮用水中铀和砷浓度的升高反映了 含水层中自然发生的浓缩，以及部落社区附近采矿留下的遗产。第2个项目： 哥伦比亚大学北部平原超级基金研究计划(CUNP-SRP)将使用同位素 U和Se的组成，因为这些元素对含水层中的氧化还原变化很敏感，以推断来源和 控制污染物暴露的过程。U和Se的氧化还原化学控制其水溶液 地下水中的浓度；被氧化的物种具有移动性和毒性，而还原的物种 不解之缘。溶解U和Se的浓度受多种过程的影响(例如，稀释、吸附、 扩散)，是地下水中氧化还原引起的命运和循环的糟糕指标。因此，核素的同位素比率 地下水中溶解的U和Se以及浓度对于研究氧化还原诱导的氧化还原是非常有价值的。 (M)动员、跟踪摄取和人类接触。我们将使用U和Se同位素比率来表征 地下水中的氧化还原反应，获取有关反应进程的独特机理信息。这些 数据将帮助我们定义本地和更远距离的来源，以及金属的运输和循环过程 北/南达科他州SHS社区内的地下水。此外，我们还将开发同位素示踪剂 受环境暴露影响的人体中铀和硒循环的影响。具体目标是：(1)确定 地下水样品中U、Se同位素比值的空间分布规律。这将使用 从项目1到U、As和Se热点内和周围的目标井的高分辨率数据和模型 同位素表征。我们还将确定这些热点周围的本地污染源和远端污染源。 (2)测定地下水中天然还原铀和硒的去除水平，并确定 基于铀和硒同位素比值时间演化的潜在砷释放条件。我们会 描述U和Se的氧化还原转化和多个地下水来源(如果有的话)的潜在混合。 (3)利用同位素示踪技术确定人体对环境污染的暴露程度。我们将开发一种 非侵入性追踪饮用水中铀和硒金属暴露的新方法。为此，我们将测量U 和尿中的Se同位素比率，以限制主要接触来源和受影响的人群 对等位线和项目3的观测数据进行浇水。我们的结果将有助于评估暴露于 危险金属混合物，受污染含水层的监测和管理，以及将暴露于 使用非侵入性诊断工具的环境源。